BayesTreePrior: Bayesian Tree Prior Simulation

Provides a way to simulate from the prior distribution of Bayesian trees by Chipman et al. (1998) <doi:10.2307/2669832>. The prior distribution of Bayesian trees is highly dependent on the design matrix X, therefore using the suggested hyperparameters by Chipman et al. (1998) <doi:10.2307/2669832> is not recommended and could lead to unexpected prior distribution. This work is part of my master thesis (expected 2016).